Quantifying Jet Structure Modification and Medium Response in the QGP Using Direct Photon-Hadron Correlations in PHENIX

The Relativistic Heavy Ion Collider (RHIC) produces quark gluon plasma (QGP), a state where quarks and gluons are not confined in hadrons. One notable phenomenon is the energy loss of high momentum partons as they pass through the QGP, fragmenting into particles collectively called a jet. To understand this energy loss, we study jet constituent and substructure modifications to differentiate energy loss models and determine in-medium transport properties. One method to measure jets is through 2-particle correlations by triggering on a high-momentum particle and analyzing the yield of associated particles based on their azimuthal angle differences. In addition to suppression of opposing high-momentum hadrons, PHENIX π⁰-hadron correlation studies show medium response significantly influences low-momentum hadron distribution. Direct-photon hadron correlations are particularly useful because unlike hadrons, photons are unaffected by the strong force and provide an unbiased trigger. These photons, reflecting the energy balance of the opposite parton from the initial hard scattering, help to accurately assess the momentum of the opposing jet. I will present the status of direct photon-hadron correlations using the highest statistics PHENIX 200 GeV Au+Au dataset.